Comparison

Multiplier vs Membership App

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Multiplier

This app automates complex calculations for predicting mature height, bone length, and limb length discrepancies in children. It simplifies manual methods, reducing calculation time and errors for various orthopedic and growth-related assessments.

Highlights
  • Predict mature height
  • Calculate bone length
  • Assess limb length discrepancy
  • Analyze growth remaining
  • Plot height on CDC charts
  • Scanogram calculations
  • Foot length analysis
Features
Read full description

The Multiplier App automates calculations to predict mature height and bone length in children. This method was created originally in Baltimore at the University of Maryland and subsequently developed at the International Center for Limb Lengthening (ICLL), Rubin Institute for Advanced Orthopedics (RIAO), Sinai Hospital of Baltimore. We have taught the Multiplier Method for more than 19 years at our annual Baltimore Limb Deformity Course (http://www.DeformityCourse.com). These calculations are typically performed by hand, using various formulae. Certain calculations are easy, but others involve more complicated formulae. Utilizing this app will reduce the time needed for these routine calculations and decrease errors. You need only input certain data (sex, age, length) and the app will calculate the answer by using the appropriate Multiplier formula. The Multiplier App will allow you to make the following calculations: LOWER EXTREMITY · Limb Length Discrepancy (LLD) (Congenital) · LLD (Developmental) · Growth Remaining · Bone Length · Timing of Angular Correction · Timing of Epiphysiodesis · Comprehensive (Congenital) LLD and Epiphysiodesis · Scanogram Calculations (Calculates femur/tibia lengths, overall limb length discrepancy, and amount/side of femur/tibia discrepancies) UPPER EXTREMITY · LLD (Congenital) · LLD (Developmental) · Growth Remaining · Bone Length Height and CDC Growth Charts (Calculates height at maturity, calculates height at every age, and plots the patient’s height and weight on the CDC growth charts) ACHONDROPLASIA · Height · Sitting Height · Leg Length Fetus (Calculates the length of tibia or femur at birth and maturity) FOOT · Foot Length · Foot Length Discrepancy · Foot Height · Foot Height Discrepancy Spine (Calculates sitting height at maturity) Oblique Plane Deformity (Calculates magnitude, orientation, and direction of an oblique plane deformity) Inclined Osteotomy (Calculates the rotational orientation and the vertical inclination of the osteotomy) This app also provides the following additional resources: · Bone Age: Elbow and Hand (Shows how to determine skeletal age by using radiographs of the elbow or hand) · Figures that show the standard measurements for the lower limb and foot · The multiplier formulae that the app uses to perform the calculations · Tables that show the multiplier values that are used in the formulae · Figures that show the Solomin Foot Analysis (Deformity correction planning for the midfoot, hindfoot, and ankle using reference lines and angles provided by Dr. Leonid Solomin) · Figures that show the development of the apophyses, epiphyses, and bones · Bibliography · User guide DISCLAIMER: No growth prediction method is 100% accurate; this App is not a substitute for sound and careful clinical judgment. PRIVACY POLICY: We respect the privacy of the people who use the International Center for Limb Lengthening apps. The Multiplier app does not collect, use, or distribute any data from the users.

About

Membership App

Connect with thousands of orthopaedic professionals, access educational resources, and manage your membership on the go. This app helps you build your knowledge and network within the orthopaedic community.

Highlights
  • Connect with 38,000+ orthopaedic leaders
  • Member-to-member direct messaging
  • Access CME and online learning
  • Manage membership details
  • Find JAAOS and podcasts
  • Access Advocacy Center
Features
Read full description

The new AAOS Membership App gives you quick access to the resources, peers, and tools that will help you build your orthopaedic knowledge and grow within your profession. Boost your network with access to 38,000+ orthopaedic leaders from around the globe in the exclusive AAOS Member Directory. Our new member-to-member direct message feature helps you quickly connect and engage. Easily find what you need most -- your CME, JAAOS, Online Learning, OVT, Podcasts, Advocacy Center, and so many more member resources. Manage your membership while on the go. Easily update your profile, disclosure and personal preferences, view and access your past purchases, pay your balance and more. We're making it as simple as possible so that you can get back to what matters most -- your patients.

Screenshots

Multiplier4 screens
Membership App4 screens

Verdict

The call

The clearest difference is review sentiment: Multiplier at 83% against Membership App's 40%. Multiplier also leads on rating (4.6 vs 3.8) and iOS requirement (13.0 vs 15.1). Membership App's advantage is monetization model (free vs paid) and update cadence (every 6 weeks vs every 7 months). On price, ratings volume, ads and in-app purchases there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Multiplier holds the better App Store score, 4.6 against 3.8. Both are backed by a comparable volume of ratings — 24 and 19 respectively. Written reviews point the same way: 83% of Multiplier's written reviews are positive against 40% of Membership App's.

UpkeepUpdate frequency

Multiplier ships an update every 7 months, Membership App every 6 weeks. The most recent releases landed on July 2, 2026 and July 21, 2026 respectively.

Scorecard5 real differences · 5 level
Multiplier versus Membership App: the parameters behind the verdict, then further details
ParameterMultiplierMembership App
PriceFreeFree
Rating4.6 (24 ratings) — better3.8 (19 ratings)
Positive reviews83.3% of reviews — better40.0% of reviews
Number of ratings24 — better19
Update frequencyEvery 7 monthsEvery 6 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidFree — better
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS13.0 — better15.1
Further details — not scored
Size62 MB49 MB
Age rating12+12+
DeveloperLifeBridge HealthAmerican Academy of Orthopaedic Surgeons Mobile

Customer experience

Multiplier

All ratings23 ratings
Positive95.7%
Neutral0.0%
Negative4.3%
Written reviews30 reviews
Positive83.3%
Neutral0.0%
Negative16.7%

Membership App

All ratings19 ratings
Positive68.4%
Neutral0.0%
Negative31.6%
Written reviews5 reviews
Positive40.0%
Neutral0.0%
Negative60.0%

In-app purchases

None

Multiplier

No in-app purchases

None

Membership App

No in-app purchases

Questions

Is Multiplier free?
Multiplier is free to download, with no in-app purchases.
Is Membership App free?
Membership App is free to download, with no in-app purchases.
Which has better reviews, Multiplier or Membership App?
Multiplier is rated higher. Multiplier averages 4.6 out of 5 from 24 ratings, while Membership App averages 3.8 from 19 ratings.
Do Multiplier or Membership App have ads?
Neither Multiplier nor Membership App shows ads.
Which is updated more often, Multiplier or Membership App?
Multiplier ships an update every 7 months, and Membership App every 6 weeks. Most recently, Multiplier was updated on July 2, 2026 and Membership App on July 21, 2026.

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